Twin compressor unit



Sept. 23, 1941. N. B. SPURGEON Em 2,256,654

TWIN COMPRESSOR UNIT Filed Feb. l, 1957 blib' A INVENTOR:

BYM/M' ATTORNEY.

rthe following description Patented Sept. 23, 12941 UNITED STATES PATENT orrics `'IWIN COMPRESSOR UNIT Neil B. Spurgeon, River Forest, andvJames H.

Cahill, Wheaton,

New York Ill., Roebuck and Co., Chica as'sgnors to Sears,

go, Ill., a corporation of Appnationrebruary 1, 1937, seria1No. 123,336

4 claims.

.the motors may be driven from an ordinary house current utilizing the standard fuses and may be started without causing the fuse to blow.

Another object is to provide an air compressor using two compressor units which may be driven separately by two split phase motors so related that the motors may be started for operating the compressors without requiring the use of a mechanical unloading clutch or air unloader.

A further object is to provide an air compressor using two separate compressor units driven by two separate motors, the motors and the units together with the related structure being so connected that the whole may be quickly and rea* sonably transported and. vibration reduced to a minimum.

Other objects and advantages will appear from and the drawing illustrating the invention. I

In the drawing:

Fig. 1 is a side elevation of the compressor unit embodying the invention;

Fig. 2 is a top plan view of the structure shown in Fig. 1; and

Fig. 3 is a diagrammatic layout illustrating the relationship between the motors and the controlling switch.

The embodiment selected to illustrate the invention as shown in the drawing comprises a pair of air compressor units I6 and I2 which are mounted on a rectangular base I4 and driven by motors I6 and I8 respectively. The motors I6 and I8 are provided with pulleys 20 which are operatively connected to pulleys 22 of the compressor units by means of belts 24 so that the compressor units may be operated when the motors are operated. The motors I6 and I8 are also secured to the base I4 by any suitable means such as bolts 26.

It will be noted that the motors and the compressors are arranged in tandem relationship so that their respective pulleys will be substantially 1n the same plane.

` 42 respectively. The

Cil

As shown in Figures l and 2 each of the compressors I0 and I2 comprises a base portion 28 and a head portion 30, which are secured together by screws 32.

The compressors I0 and I2, together with the motors I6 and I8, are not, in themselves, the object of the present invention but rather the invention is directed to the novel combination and, relationship of these component parts together with the inclusion of certain other elements for providing a compressor having the characteristics set forth hereinbefore.

Consequently, different types of compressors and motors per se may be utilized, but for the purpose of the present disclosure and in present practice, it has been found expedient to utilize compressors of the type illustrated and split phase motors.

The compressors I0 and I2 and their top portions are Xedly and rigidly connected by means of a pair of spaced apart connecting plates 34 which are secured to the compressors by means of the bolts 32 used for connecting the heads 36 of, the compressors with their respective'base portions.

l The extreme sides of the compressors I0 and I2 are also provided with U-shaped handle portions 36 connected thereto by `certain of the bolts 32 so' that the unit as a whole may be manually moved from place to place. As shown in Figures 1 and 2, each of the compressors I0 and I2 is provided with an air intake 31 and also with air outlets to which are connected pipes 46 and pipe line 42 connects with the pipe line 4i) and is provided with a check valve 44 so that air can pass only from the pipe 42 into the pipe 40 and not back towards the compressor I2. The pipe 45) in turn is connected with an expansion chamber 46 which in turn is provided with a pressure indicator 48 and an air hose 50.

The rectangular base or carriage I4 on which the above described structure is mounted is preferably formed from sheet steel having the ends and sides bent downwardly at substantially right angles to provide a relatively platform. The rigidity of this ther enhanced by provision of a stiffening bar 52 such as an angle bar extending longitudinally on the under side thereof, as shown by dotted lines inFigure 2. I

As clearly shown in Figure 1, the supporting platform I4 is mounted on rollers or casters 54 so that the carriage may be easily transported. It will be noted that the casters 54 are positioned substantially midway between the compressors and their respective motors, thereby tending to balance and provide a uniform distribution of the load of theV compressor as a unit, thereby re- 'ducingl any vibration to a minimum which mayv be set up as a result of the operation of the compressors and the motors.

the other lead-in line B in lhirillnioatioh Withlaf switch contact 62. Switch contacts 64 and 66are in communication'with the motor I6. The switch l comprises two insulated vmembers 'l2 :and 14 whichA are rotated simultaneouslywhen the switch knob is turned. The switch member T2 is provided with contacting portions 16 and 148 and the switch member 14 is likewise -providedjwith contacting portions 80 and 82. Y

Figure 3V shows VVthe relative vpositionsofil the rotatable members 12' and 14 when the circuit is open and themot-ors are not functioning. When it is desired to start the motor 'i6 for operating the compressorlli, the-switch is kturned for ro- .tatingthemembers l2 and 14, causingA the contact i6-to moveintongagement with the contact and the contact i8 `to move out of vengagement with the contact 8,4. -At the same time the member i4 is rotated the contacts 80 and 82 move out of engagement withjthe contacts ll) andV 66 vand into engagement withthe contacts G GYand 62 respectively, thereby starting the motor; I6 for operating the compressor'lil. When thefmotor I6 and the compressor lil are operating at 4full speed the switchlinob is again rotated for rotating. the members "I2 and 14, thereby causing the contacts i6 and 'I8 of the member 12 toengage the contactsy 6 4 and 6;3 respectively, and v'atfther same timelto rotate thelmemberl' so that; the

contacts BB and S2- will engage the contactsBZ and 1D respectively, thereby starting theV motor I 8jand the compressorgl'z, the engagement ofthe ycontactsild and 68 withth'emember 12 insuring the continued` operation ofy the, motor |16 "and compressorrnli Y Y' Thus it will'be seen that one motor and compressorrmay be started yand allowed to reach; its

maximum speed before start-ing the` othermotor Y and compressor, which prevents the .poweri line from being overloadedv and causing the fusesto blow out such aswould happen. if the. motors were started simultaneously.l The -motors,1 of

course could be started simultaneously providedv thatfuses having a higher capacity were used,

the use of such fuses lon low Voltage lines results in dangerof burning out themotordue .to the 'fact that there is Anot enough voltagelto turnthe motor. The over-fusing of the electrical circuit is also dangerous as a fire hazard and further objectionable by reason. of the fact lthat ituma'y cause arflickering of Ylights'in neighboring lines withconsequent complaints. The uti- 'liz'ationof this circuit for starting'the motors separately also enables ,sp1it;phase motors to. be utilized'which otherwise would not be possible inplace.

asmuch as such motors have poor starting characteristics.

It will also be noted that when the compressor I0 is in operation prior to the operation of the compressor l2, the pressure of the air from the compressor lll is prevented from being transmitted to the compressor l2 by reason of the check valve 44 lso that the compressor l2 may be started .without being subjected to a starting load.

Thus it will'be seen that a compressor is pro- `vided for supplying a stream of air under pressure with a maximum of efliciency, that it is adaptable for use with a low voltage line, and

' maybe quickly: andveasily moved from place to Furthermore, the several members are so arranged and connected that the unit as a whole will loiie'r little, if any, vibration.

Y We claim:

1.. In; combination, a platform, a pair of motors,'a pair of air compressors mounted on the platform and provided with pulleys', belt/means lconnected `with tthe pulleys of the 'compressors 4and the motors whereby thecompressors may be operated when the motors are run,`saidmotors and compressors being arranged vvin tandem and the pulleys `thereof disposed substantially inthe same plane, andfmeans comprising rollers mount- 'ed on the under 'side of said rplatform whereby the platform may be transported, vsaid rollers being positioned substantially midway between the compressors and 'the motors.

l2. In combination, aSpai-r offcompressorsgpow- 'er meansxoperatively'connected with the'com'- ing'the passage of 'ai-rfro'm tlieexpansion eha'mber tok one'fof the 'compressors when Vone "of the compressors is not inf operation and'means' for so actuating said' power means that Asaid othercompresser' is first vplaced in operation alone and thereafter 'said one compressor isv placed Sin operation'without stopping said other compressor.

3; In combination, a base, *a pair Y'of 'spaced apart` air compressors lmounted on' the base, power means for operating the compressors, -sa-id compressors having conduits connected therewith for`providing communication therebetween, each of said compressors comprising fa-baseportion and a head portion, screws `for"-vgzo'nneci'ling lthe head portions with thebase'portions, and a pair of spaced apartfplate'membersdisposed between the compressors, zsaid screwsbeing 'adapted for xedly connecting theV plate members with the compressors for-providing a rigid connection therebetween. Y 4. In combination, a support, a f'pair oflspaced apart independently 'operated compressorsys'eparately mounted "onfsai'd support and having c'onduits 'connected tl'ie're'with for providing communication' therebetween, i'each of v said compressors comprising a baseportion fand a headportion, means connecting sa-id vportions 'of' each compressor'v together,y "andri'gid connectingV means bridging th'e vspace' between said corripressors,- the rst means -fixedly"'ccrmeet'ing` the secondmeans with the Compressors forf'provi'ding a rigid connection therebetween. y n

NE1L njsrunonoN. 

